Enforcing pull request workflow and green CI status of PRs

I believe I ran into some problems because of this new gating.

This build:

threw a warning:

INFO    src.manifest: Checking 1 external data items
INFO    src.manifest: Started check [1/1] archive sweethome3d/SweetHome3D-7.0.2-linux-x64.tgz (from com.sweethome3d.Sweethome3d.json)
ERROR   src.manifest: Failed to check archive sweethome3d/SweetHome3D-7.0.2-linux-x64.tgz with HTMLChecker: Error querying for new versions: Connection timeout to host http://www.sweethome3d.com/history.jsp
WARNING src.main: Check finished with 1 error(s)

and was never published.

There are no notifications of any kind from the build system that the build failed, so for a week, I thought SweetHome3D had had its runtime updated within a couple of hours of me merging the changes in:

A week later somebody filed a new issue about it: